MODERN LIVING: Dry-Land Cruise

J. P. Morgan was once asked by a friend: "How much does it cost to run a yacht?" Boomed the great J.P.: "Sir, if you have to know how much it costs, you shouldn't own one." Last week, as the 43rd annual Motor Boat Show opened in Manhattan's Grand Central Palace, it was evident that Morgan's rule of thumb no longer applied. In the biggest show in history, 248 exhibitors displayed boats for every pocketbook—from $39.95 for a shrimp boat to $72,700 for a cabin cruiser.

For those who like to pinch pennies in their own workshops, the build-it-yourself business...